Electrical connector



June 11, 1957 J. SCHMIER 2,795,767

ELECTRICAL CONNECTOR Filed Aug. 18, 1955 3 Sheets-Sheet 1 3 FIGB,

INVENTOR. JACOB SCHMIER Ly? i ATTORNEY June 11, 1957 J. SCHMIER 2,795,767

ELECTRICAL CONNECTOR Filed Aug. 18, 1955 3 Sheets-Sheet 2 INVENTOR.

JACOB SCHMIER ATTORNEY June 11, 1957 J. SCHMIER 2,795,767

ELECTRICAL CONNECTOR Filed Aug. 18, 1955 3 Shee ts-Sheet 3 INVENTOR. JACOB SCHMIER BY C 2 2 A TORNEY United States Patent C ELECTRICAL CONNECTOR Jacob Schmier, Allentown, Pa., assignor to Rodale Manufacturing Company, Inc., Emmaus, Pa., a corporation of Pennsylvania Application August 18, 1955, Serial No. 529,149

3 Claims. (Cl. 339-76) My invention relates to a quick detachable electrical connector of either the two, three, or more wire-type, which may be used for carrying a heavy current load for household and commercial devices such as electric dryers, or for industrial devices such as portable electrical devices.

The connector which forms the basis of this invention is one wherein the cap and complementary connector body are joined to each other by a straight insertion and/or a twist to lock the cap and connector body together. Both the cap body and the connector body of my invention are made entirely of soft rubber rather than of the usual rigid type of thermosetting plastic such as phenolic condensation products or the like, this soft rubber body being resilient and unbreakable.

It is an object of my invention to provide an electrical quick detachable connector having a separable sleeve of unbreakable flexible rubber wherein the sleeve completely envelops the connector terminals and wherein the separable sleeve is readily attached to or detached from the main body portion of the connector.

Another object of my invention is to provide an electrical connector having a flexible rubber insulated connector body and sleeve which will not crack, break, or chip.

Another object of my invention is to provide a quick detachable connector whereby polarized blades of a cap may be inserted into the connector body in only one predetermined position.

Another object of my invention is to provide a quick detachable connector whereby polarized blades, either of the straight plug or the interlocking type, will always be maintained in a predetermined position.

Another object of my invention is to provide a quick detachable connector body of soft rubber, whereby a hard insulating washer or disc having predetermined blade openings therein cannot be stretched, whereby electrical connections may be made only in one predetermined position.

Another object of my invention is to provide an electrical terminal held together by a square shank holding rivet to prevent the terminal from swinging, turning, or oscillating about the holding rivet.

Other objects of my invention are to provide an improved device of the character described, that i easily and economically produced, which is sturdy in construction, and which is highly effective in operation.

With the above and related objects in view, my invention consists in the details of construction and combination of parts, as will be more fully understood from the following description, when read in conjunction with the accompanying drawings, in which:

Fig. l is an exploded view of the connector showing the cap, the connector body insulating sleeve, and the connector separated from each other.

Fig. 2 is a side view showing the plug cap connected to the connector body, and showing the intervening sleeve in outline.

2,795,7 6? Patented June 11, 1957 Fig. 3 is a fragmentary side view of the cap wherein the cap has been twisted into locking arrangement with the connector body, and wherein the connector body sleeve is omitted.

Fig. 4 is a perspective View of the connector body itself.

Fig. 5 is an end view of the conector body shown in Fig. 4.

Fig. 6 is a sectional view taken along the line 6-6 of Fig. 2.

Fig. 7 is a sectional view taken along the line 7-7 of Fig. 3.

Fig. 8 is a perspective view of a contact terminal showing the contact formed of a plurality of spring contact members held together by a square rivet.

Fig. 9 is a perspective view showing a contact guard wherein the guard is held to its base by a square rivet.

Fig. 10 is a fragmentary side view showing a cap connected to a connector body wherein a modified type of flexible sleeve is shown broken away. The cap and receptacle body are in the act of being interconnected, and the connector body represents a modification of the connector body shown in Fig. 4.

Fig. 11 is a view analagous to Fig. 10, but wherein the cap has been twisted so that the cap and the connector body cannot be disconnected by pulling the cap and con nector body apart in a linear direction, and wherein a cap of a predetermined construction only can be used.

Fig. 12 is a sectional view taken along the line 12-12 of Fig. 10.

Fig. 13 is a sectional view taken along the line 13-13 of Fig. 11.

Fig. 14 is a sectional view taken along the line 14-14 of Fig. 10.

Fig. 15 is a perspective view of another modification of a spring contact and its base, which are to be held together by a square rivet.

Fig. 16 is a perspective view of the integrally formed detachable flexible sleeve, having one end wall with openings therein to admit cap terminals and individual insulator plates and metal plates, each of the plates having an opening therein to enable a single cap blade to pass therethrough and through one of the aligned end wall openings.

Fig. 17 is another modification of my invention wherein the flexible sleeve has a single insulator disc with three slots positioned thereon to enable a cap terminal with three terminals to pass therethrough and through one end of the flexible detachable sleeve.

Fig. 18 is a sectional view taken along the line 18l8 of Fig. 17.

Fig. 19 is a sectional view taken along the line 1919 of Fig. 17.

Fig. 20 is a perspective View of an insulator disc having three slots therein for permitting three prongs of a polarized cap therethroug Fig. 21 is a perspective view of the flexible sleeve.

Referring now in greater detail to the drawings, wherein similar reference characters refer to similar parts, I show a quick detachable connector comprising an electrical cap or plug, generally designated as A, which is adapted to be attached or connected to a complementary connector body or receptacle body, generally designated as B. A flexible insulating sleeve of soft rubber,

generally designated as C, may be readily attached to or detached from the receptacle B in order to easily attach wires (not shown) to the receptacle. The plug and the receptacle body are adapted to be quickly coupled together to serve, when properly wired, as electrical conductors in an electrical circuit.

The cap A comprises a cylindrical body 10 made of flexible insulating material, such as soft rubber, which is unbreakable. A plurality of blades, prongs, or terminals, each designated 12, have one of their ends connected to the unbreakable cap body by suitable bolts, while the free end serves as an electrical contact. A hook 14 is provided on the free end of each blade for locking purposes and the hook extends at right angles to the main portion of the blade. integrally formed with its hook portion 14 which also is arcuate. An insulating cover or disc 15 closes the front end of the cap A in order to cover the electrical wires (not shown) to which the blades are wired.

The complementary receptacle or connector body B comprises a cylindrical body 16 made of flexible material, such as unbreakable soft rubber, having a bore 19 centrally therethrough for the purposes of allowing electrical lead wires (not shown) to pass through the bore within the receptacle body 16 and to be connected to binding screws 20 provided in an electrical conducting holding plate 21, which is fastened in the connector body by a rivet or a grommet 18.

A plurality of electrical repectacle contacts or terminals, generally designated as D, on the receptacle body B (Fig. 4) corresponding in number and position to the electrical prongs 12 is formed by base plate 21 and a rigid guard contact D1. The contact D1 is engaged by the cap blades 12. The terminal D (Fig. 9) has a main base 21, and an extended guard contact or terminal or prong D1 which is held to the base 21 by a square rivet or grommet 13 to prevent twisting or turning of the respective members with respect to one another. The guard prong has an extension 22 which projects at right angles to the base 21, and integral with but perpendicular to the free end of the extension 22 is: a hollow flange or rim 24 having a continuous square rim. The flange opening 26 of the square rim 24 permits only a complementary prong or blade to pass through the opening in order that the proper prong 12 of the cap engages the contact 22 of the connector.

To provide an excellent contact, I use a spring contact arm 282 which is connected at one end to the base plate 21 and the arm 28 extends parallel to the blade terminal D1 so that each spring arm 28 is parallel and adjacent to its complementary terminal D1. The cap blade 12 enters the guard opening 26 and is spring pressed by the legs 22 and 28 of the connector body to insure an excellent electrical contact.

The flexible rubber sleeve C is provided with a plurality of longitudinal openings 30 which extend through the length of the sleeve, and these openings are adapted to receive the connector body terminals D1 and their respective spring contact members 28; and the sleeve C is connected to the connector body 16 by a plurality of screws 32. This sleeve C extends beyond the terminals D and is adapted to completely enclose the blades or the terminals D as well as the prongs 12 of the cap A when it is connected to the connector body B. Hence, the sleeve acts as an insulator for both sets of terminals.

In the case where one of the terminals serves as a ground connection, then the shape or size of the blade or prong guard 24 may be different in size or shape than the other guards so that the grounded cap can be coupled to the correct connector body in but one position.

Hence, the square prong guard 24 serves to prevent improper blades of a plug from being incorrectly inserted into the receptacle body. This construction prevents the blowing of fuses or otherwise injuring the electrical apparatus where an effort is made to improperly join connected parts of a circuit.

,Cto the base Bp a In operation, the cap -A is electrically connected to a connector bodyB by inserting the blades 12, 12 between the terminals D and the spring-like contact 28, the spring 28 acting to hold the prongs 12 against the blade 22.

Each of the blades 12 is arcuate and is The cap is then turned or twisted relative to the plug and this causes the hook portions 14 to interlock with the guard rim 24 so that neither the cap nor the connection can be pulley axially away from one another, but to unlock them it is necessary to twist them so as to unlock the hooked portions. e

The all flexible rubber plug and terminal to terminal locking contacts possess the following advantages: (l) is unbreakable and shockproof; (2) is easier to manufacture and assemble; and (3) is easy for the electrician to wire.

in the case of polarized blades, it is necessary for the blades to enter the connector in a predetermined relationship. For example, one terminal may be to a live or positive side of the electrical circuit, and the other side may be to the grounded or the negative side of the circuit. It is imperative that the correct polarity be maintained.

In Fig. 8 is shown a plurality of conductive spring blade receiving arms 34, 36, and'38, which are adapted to be attached to a common base 40. A square opening 42 in the base and in the arms 34, 36, 38 is adapted to receive a square-shank holding bolt or rivet 13 which, when peened over, holds the arms and prevents them from twisting.

In Fig. 15 is shown a base 21 to which a spring contact 44 is adapted to be held by a square rivet or grommet 13.

Referring now to a preferred embodiment of my invention, I show, in Figs. 10 to 14, and Fig. 16, inclusive, the cap or plug A and the complementary receptacle B, wherein the receptacle B has a polarization guard formed in a sleeve, generally designated as C1.

In Figs. 10 to 14, and Fig. 16, I show the flexible sleeve C1 with a cylindrical outer wall; and an integrally formed end wall 31 at one end of said outer wall with openings 31A, 31A therein only for the purpose of permitting plug terminals to pass through the'end wall to enter the openings. The end wall 31 substantially closes one end of the flexible rubber sleeve as well as the openings 30, 30; while the other end of the sleeve C1 is substantially open to enable the blades D to enter therein so that the blades are covered by the sleeve C1. The two openings 30, 30 in the flexible sleeve C1 are spaced apart by a dividing wall or barrier 30B and each opening 30 is defined by chamber walls, 30C, 30D, 30E, and 30F, Figs. 12 and 13, which define one of the rectangular openings 30 in the flexible sleeve.

The outer end wall 31 has the small rectangular metal plate F abutting it, the edges of the plate F engage the walls defining the opening 30. The opening 46A in the metal plate F is aligned with the opening 31A in the end wall to permit the correct cap blade to pass therein. In parallel engagement with the metal plate F in a molded insulator plate E which prevents any short circuits between the metal plate and the terminal of the cap. For example, if a cap having improperly aligned terminals for the receptacle were to be forcefully pushed into the receptacle body, the terminals on the cap might push the metal plates F against the receptacle blade thus completing an electrical contact provided the insulator plate E were not used. However, the insulator plate prevents undesired electrical contact between the cap prong and the receptacle contact.

The flexible sleeve C1 is adapted to cover or surround the interlocking terminals 12 and 44. The flat end wall 31 of the flexible sleeve C1 has openings 31A therein for the cap prongs, and aligned therewith is a rigid insulator plate, generally designated as E, with an opening 46 therein. The opening 46 is adapted to receive the terminals 12 of the cap. Reinforcing the border of the openings 46 is a metal plate, generally designated as F, which has an opening 46A therein with the opening 46A aligned with the opening 46. Likewise, an opening 48A in a second metal plate F is aligned with an opening 48 in a. second insulator plate E.

The metal insert F would prevent the rim of the opening of the insulator E from shattering, since it strengthens the periphery of the opening in the insulator plate E. Furthermore, if a person were to use a non-complementary cap which is not adapted to interfit into the connectory 'body, he could not force the cap into the receptacle, thereby precluding shattering or enlarging the openings in the insulator plates E, E.

In Figs. 17 to 20, I show another modification of my invention wherein an insulator disc, generally designated as F2, interfits with a soft, flexible insulating sleeve, generally designated as C2. The insulator disc F2 is complementary to a three terminal sleeve C2 which has openings therein to be aligned with the openings 50, 51, and 52 in the disc F2. A central projection 54 on the sleeve C2 has a plurality of radially extending walls 54A to serve as guards to prevent arcing from occurring between the terminals when the circuit is broken.

The disc F2 interfits with a complementary recess 56 in the sleeve whereby the openings 50, 51, and 52 will be aligned with properly aligned openings in the face of the sleeve C2. It should be noted that the arcuate opening 50 in the insulator disc F2 is wider than the arcuate openings 51 and 52, so that the prongs from a cap going into the respective openings are of dilferent sizes. This construction is preferred where one terminal may be for the ground connection. A projection 58 on the sleeve C2 aligns the disc F2 when the peripheral notch 58A interfits therewith so that the openings for the cap prongs on the outside surface 60 of the flexible sleeve insulator C2 are in correct alignment with the openings 50, 51, and 52 on the insulator disc F2.

The flexible insulators C1 and C2 have an internal cavity and a closed outer face or surface 60 for either two, three, or more openings therein so that the user is safeguarded from coming in contact with any live circuit and only the proper cap prongs may be inserted therein.

Although my invention has 'been described in considerable detail, such description is intended as being illustrative rather than limiting, since the invention may be variously embodied, and the scope of the invention is to be determined as claimed.

I claim as my invention:

1. An electrical receptacle comprising a body portion having a plurality of projecting spaced terminal-s connected to said body portion, a flexible rubber sleeve having a plurality of openings wherein each opening is defined by a chamber surrounding each receptacle body terminal, a wall integrally formed with one end of said sleeve to substantially close said one end, means to detachably connect said flexible sleeve to said receptacle body, said sleeve extending beyond said receptacle terminals and completely enveloping said receptacle terminals, each terminal of said receptacle body being completely housed within one of said sleeve openings, a metal plate mounted adjacent said sleeve wall within one of said openings, an insulator plate mounted adjacent to and in engagement with said metal insert; the said metal insert, said insulator plate and said sleeve wall having aligned openings for the penetration therethrough of a detachable terminal whereby said metal plate prevents the unauthorized spreading of the opening in said flexible sleeve and of said plate.

2. An electrical connector comprising a cap and a receptacle, said cap having a plurality of terminals, said receptacle consisting of a body portion having a plurality of terminals connected to said body portion, a flexible rubber sleeve having a plurality of openings wherein each opening is defined by a chamber surrounding each receptacle body terminal, a wall integrally formed with one end of said sleeve to substantially close said one end, means to detachably connect said flexible sleeve to said receptacle body, said sleeve extending beyond said receptacle terminals completely enveloping said receptacle terminals, each terminal of said receptacle body being completely housed within one of said sleeve openings, a metal insert mounted adjacent said sleeve wall within one of said openings, an insulator plate mounted adjacent to and in engagement with said metal insert, and said metal insert, said insulator plate and said sleeve wall having aligned openings for the penetration therethrough of one of said cap terminals whereby said metal plate prevents the unauthorized spreading of the opening in said insulator plate.

3. An electrical receptacle comprising a 'body portion having a plurality of projecting spaced terminals connected to said body portion, a flexible rubber sleeve having a plurality of openings wherein each opening is defined by a complete chamber surrounding each receptacle body terminal, a wall integrally formed with one end of said sleeve to substantially close said one end, means to detachably connect said flexible sleeve to said receptacle body, said sleeve extending beyond said receptacle terminals and completely enveloping said receptacle terminals, each terminal of said receptacle body being completely housed within one of said sleeve openings, a metal plate mounted adjacent said sleeve wall withing one of said openings, an insulated plate mounted adjacent to and in engagement with said metal insert, and said metal insert, said insulated plate and said sleeve wall having aligned openings for the penetration therethrough of one of said cap terminals, whereby said metal plate prevents the unauthorized spreading of the opening in said flexible sleeve and of said plate.

References Cited in the file of this patent UNITED STATES PATENTS 1,646,037 Meuer Oct. 18, 1927 1,771,729 Hubbell July 29, 1930 1,938,039 Propp Dec. 5, 1933 1,944,517 Knutson Jan. 23, 1934 1,965,594 Hubbell July 10, 1934 2,127,544 Von Holtz Aug. 23, 1938 2,220,810 Bright Nov. 5, 1940 2,677,115 Stevens Apr. 27, 1954 2,703,871 Woodhead Mar. 8, 1955' 2,724,808 Schmier Nov. 22, 1955 

